WO2003077577A1

WO2003077577A1 - Method for monitoring a interface circuit in wireless communication system

Info

Publication number: WO2003077577A1
Application number: PCT/CN2003/000131
Authority: WO
Inventors: Zhili Xia
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2002-03-13
Filing date: 2003-02-14
Publication date: 2003-09-18
Also published as: AU2003211852A1; CN1223213C; CN1444410A

Abstract

The present invention discloses a method for monitoring A interface circuit in wireless communication system, in each TRAU unit it set an persistent unactivated state timer of TRAU unit, for which an operation and maintenance unit of Base Station Controller (BSC) set a threshold value; simultaneously, set said timer to remain in nontiming state when the TRAU unit performs regular service, to start timing when the TRAU unit is set in nonservice state, and to remain in timing state during the TRAU unit is in nonservice state; when for said timer current timing value is equal to the threshold value being set, the TRAU unit reports the timeout information for locating the problems occurring in A interface circuit. Thus, abnormality that causes A interface circuit unusable, and break of upstream landline transmission from the BSC to the TRAU unit for various reasons, can be identified in time, to avoid wasting A interface circuit resources, to increase access success ratio in busy period, and to improve service quality and maintainability for Base Station Subsystem and even wireless communication network.

Description

Method for monitoring A interface circuit in wireless communication system

The present invention relates to an interface circuit monitoring technology for a wireless communication system, and in particular, to a method for monitoring an A interface circuit between a base station subsystem (BSS) and a network subsystem (NSS) in a GSM communication system. Background of the invention

A complete GSM local network system usually includes two parts: BSS and NSS. BSS consists of a base station system (BTS), a base station controller (BSC), and a code conversion and rate adaptation unit (TRAU). The NSS consists of mobile switching. The center (MSC), the visitor location register (VLR) and the home location register (HLR) are composed of other parts. The interface between BSS and NSS is the A interface, and the A interface is an open standard interface. BSS products and NSS products produced by various equipment manufacturers must support this standard interface, so that BSS products and NSS products from different manufacturers can be interconnected. To form an integrated GSM network.

In the actual GSM networking, a single BSS or multiple BSS systems can be used as a local network, subordinate to the local mobile operating entity, and its corresponding NSS network can be a remote mobile operating entity. For the A interface circuit between BSS and NSS, BSS acts as its slave and NSS acts as its master. When NSS places some A interface circuits in an abnormal state for some reason, such as: out of step, abnormally busy State, even if the A interface circuits corresponding to the BSS side are in a normal state, these circuits will be unavailable for a long time. The BSS system cannot identify these abnormal A interface circuits, thus leaving expensive circuit resources idle. In severe cases, it can cause network congestion, and a large number of calls cannot be connected, which greatly affects the quality of service of the network and causes great economic and reputational losses to the BSS operator. However, the NSS operator, which is the root cause of such problems, has no benefits. Get hurt, so often do n’t take the initiative This kind of exception. Such problems often occur on the GSM network, but there is no proper way to deal with this in existing equipment.

In actual GSM products, there are basically two ways to implement the TRAU unit: one is the resource pool method, and the other is the embedded method. No matter how the TRAU unit is implemented, the TRAU unit logically belongs to the BSC, and its operation and maintenance is performed by the BSC. For a TRAU unit implemented in an embedded manner, the TRAU unit exists on the A interface circuit between the MSC and the BSC, and there is a corresponding TRAU unit on each A interface service circuit. In order to save transmission loss, the physical equipment of the TRAU unit should be as close to the MSC side as possible. The transmission, multiplexing, and demultiplexing equipment must be passed between the TRAU unit and the BSC. The physical connection is complicated, and it is easy to cause transmission problems, which makes various services impossible. For example: single-pass, dual-pass and data service calls cannot be performed, etc., which affects network service quality.

At present, for the above two types of problems, the BSS system lacks effective monitoring methods. For the second type of problem, that is, the situation where the A interface circuit of the TRAU unit is prone to transmission problems, you can only rely on the complaints of online users to find the problem. After the user complains that such problems are detected, the maintenance staff manually dials the measurement position, which is efficient. low. For the first type of problem, that is, the BSS system cannot identify the abnormality of the A interface circuit. If the NSS side does not actively detect the state of the A interface circuit in time, unless the abnormality is serious, causing a network congestion accident, the user can be informed by complaining to the BSS operator. Otherwise, when only part of the A interface circuit is unavailable, the BSS system maintenance personnel cannot detect such problems, which will cause the waste of A interface circuit resources and reduce the call connection rate during busy hours. Summary of the Invention

From the above analysis, it can be seen that the main object of the present invention is to provide a practical method for monitoring the A interface circuit in a wireless communication system, which can timely identify various abnormal conditions that cause the A interface circuit to be unavailable, and accordingly, the corresponding A Interface circuit is maintained to avoid A connection Interface circuit resources are wasted and idle, which improves the busy-hour connection rate and improves the service quality of the BSS network. At the same time, the invention can also identify the upstream ground circuit between the BSC exchange unit and the TRAU unit due to various software and hardware reasons. Transmission interrupted.

The method provided by the present invention includes the following steps:

a. Set a TRAU unit continuous inactive timer in each TRAU unit, and set a threshold for the timer by the BSC operation and maintenance unit. The timeout threshold of the timer is configured by the BSC operation and maintenance unit, which can be set to 24. Hours, the TRAU unit can be a TRAU unit implemented in an embedded manner;

b. When each TRAU unit receives service frame information from the BTS side, it starts normal services through in-band activation, that is, basic user-oriented services, such as voice and data services;

c. During the normal business process of the TRAU unit, the timer always maintains an untimed state;

d. When the TRAU unit does not receive service frame information from the BTS side for a period of time, the TRAU unit is set to a non-service state;

e. The timer starts counting from the non-timed state when the TRAU unit is set to the non-business state. During the time that the TRAU unit is in the non-business state, the timer keeps timing and keeps the timing state;

f. When the timer value is equal to its timeout threshold, the TRAU unit reports a timeout message to the BSC control unit through the TRAU uplink maintenance channel, indicating that the corresponding TRAU unit has not received the BTS uplink service information for the time set by the timer timeout threshold. The abnormal production is forwarded to the BSC operation and maintenance unit, and the BSS maintenance personnel locates the A interface circuit in question according to the timeout message.

The timeout message reported by the TRAU unit carries the identifier corresponding to the TRAU unit or pair. Various parameters and information of the A interface circuit should be used. These parameters and information are forwarded to the BSC operation and maintenance unit as supplementary information. In short, the timeout message forwarded to the BSC operation and maintenance unit contains as many information parameters as possible that identify the corresponding TRAU unit or the corresponding A interface circuit.

The method of the present invention further includes the following technical features: In the entire GSM system, the A interface circuit between BSS and NSS is selected for use with a certain cycle period.

The timer's timeout threshold is greater than the maximum time interval at which the corresponding A interface circuit is repeatedly selected in a cycle. At the same time, it should not be too large, otherwise, if there is a problem with the A interface circuit or related physical connection, it will delay the discovery of the problem. The specific overtime threshold is determined on the principle that no false alarms occur, the complexity is not high, and the aforementioned problems can be identified in a timely manner.

When setting the threshold setting of the timer, the BSC operation and maintenance unit sends the timer configuration information to the BSC control unit through the BSC control unit downlink maintenance channel, and the BSC control unit forwards the configuration information to each A interface through each TRAU downlink maintenance channel. TRAU unit corresponding to the circuit.

During the timing of the timer, if the BSC recognizes that the A interface circuit relay device is faulty, or performs block maintenance operations on the A interface circuit, or receives a message from the MSC to block the A interface circuit, the relevant A interface circuit status is set to non- The idle state, and at the same time, the BSC control unit issues a command to stop the timer to the timer through the TRAU downlink maintenance channel of the TRAU unit corresponding to the relevant A interface circuit. The timer of this part of TRAU unit is always in the non-timed state, so as not to generate false alarm messages in this part of TRAU unit.

When the timer is in a non-timed state, if the BSC recognizes that the A-interface circuit relay equipment is restored, or performs maintenance operations on the A-interface circuit, or receives a message from the MSC to unblock or reset the A-interface circuit, the relevant A is set. The state of the interface circuit is idle, and at the same time, the BSC control unit issues a command to start the timer to the timer through the TRAU downlink maintenance channel of the TRAU unit corresponding to the relevant part A interface circuit. Make this part of the timer count from the cleared state. When the BSC control unit does not receive the BTS uplink service information message within the time set by the timer threshold, the BSC control unit sends a reset message corresponding to the A interface circuit of the TRAU unit to the MSC side, and causes the BSC on both sides of the A interface circuit And the state of the MSC is set back to the idle state to restore these problematic A interface circuits. Avoid that the A interface circuit is unavailable for a long time due to an abnormality on the MSC side, so as not to waste related A interface circuit resources.

If the BSC control unit cannot receive the uplink service information sent by the BTS after exceeding the threshold setting time of the timer, it can send a timeout message to the BSC control unit through the TRAU uplink maintenance channel at a certain period. The sending period setting of the timeout message should consider the processing capacity of the BSC control unit and the overall alarm message volume.

The monitoring method of the A interface circuit corresponding to the embedded TRAU unit can be automatically identified in time

The A interface circuit is unavailable due to software and hardware reasons, and has a 100% failure detection rate. Therefore, in the case where the A interface circuit is unavailable due to various reasons, the A interface circuit resources are wasted for a long time, the maintainability of the BSS system is improved, the quality of service of the wireless communication network is reduced, and the cost for solving the problem is reduced. The quality requirements of the maintenance personnel configured for Class A interface problems. Brief description of the drawings

Figure 1 shows the basic components of a complete GSM local network system;

Figure 2 is a schematic diagram of the monitoring method of the A interface circuit of the GSM communication system. Mode for Carrying Out the Invention The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

The basic diagram of a complete GSM local network system is shown in Figure 1. It includes: BSS10 and NSS11. BSS10 consists of BTS1, BSC2, and TRAU unit 3. NSS11 is composed of MSC5, visited location register (VLR) and home location register (HLR). The interface between BSS10 and NSS11 is A interface 4.

The schematic diagram of the A interface circuit monitoring method of the GSM communication system is shown in Figure 2. The solid part is the design of the relevant part of the GSM system that needs to be changed in order to implement the A interface circuit monitoring function; the dotted part is the part that requires participation but does not need to make design changes in the implementation of this monitoring function. These parts only implement its The original basic functions are sufficient.

The routing mode of the A interface is set to the circular selection mode. In this mode, during the normal operation of the GSM system, the A interface circuit corresponding to each TRAU unit is cyclically used at a certain period, which is closely related to the traffic volume. If the amount of traffic is large, the selection period of the A interface circuit is short, and each A interface circuit is used more frequently. The corresponding TRAU unit 3 will be frequently activated by the uplink service information sent by the BTS1 side. On the contrary, the amount of traffic is small. The selected period of the A interface circuit is long, and the period in which the corresponding TRAU unit 3 is activated by the uplink service information sent by the BTS1 side will also be extended.

In the abnormal situation that some A interface circuits are unavailable due to various software or hardware reasons or transmission interruption between the TRAU unit 3 and the BSC2 switching unit, the corresponding TRAU unit 3 cannot receive the uplink service information sent by BTS1 So it cannot be activated. The so-called activation means that when the corresponding A interface circuit changes from the idle state (IDLE) to the busy state (BUSY), the TRAU unit 3 changes from the non-service functional state due to receiving various types of uplink service frame information sent by the BTS1. It is a service functional state, and performs code conversion of voice services and rate adaptation of data services.

Based on this principle, a timer is set in each TRAU unit 3, which is called the TRAU unit continuous inactive state timer. The timeout threshold setting of this timer should be greater than the corresponding A interface circuit where the TRAU unit 3 is located. time interval. When each TRAU unit 3 receives service information sent from the BTS1 side, such as: various TRAU service frames, through in-band activation, when normal services are started to be implemented, such as code conversion or rate adaptation, and TRAU The unit continuously clears the inactive timer; and, during the normal service process of the TRAU unit 3, it always remains cleared; when the TRAU unit 3 is released, the corresponding A interface circuit changes from the busy state to the idle state, The TRAU unit keeps the inactive timer cleared. When the TRAU unit 3 is in the inactive state, the TRAU unit continues to inactive the timer. When the timer value equals its timeout value, the TRAU unit 3 reports to the control unit 21 of the BSC2 through the TRAU uplink maintenance channel 25. The timeout message indicates that the corresponding TRAU unit 3 has had the duration of the timer timeout threshold setting and did not receive an abnormal occurrence of the BTS1 uplink service information. The control unit 21 of the BSC2 forwards the message to the BSC2 through the uplink maintenance channel 24 of the BSC control unit. Operation maintenance unit 22 for BSS system maintenance personnel to view.

The timeout message reported by TRAU unit 3 carries parameters identifying the corresponding TRAU unit 3 or the corresponding A interface circuit; when the control unit 21 of BSC2 forwards the timeout message to the operation and maintenance unit of BSC2, it obtains the physical channel from the timeout message obtained. Obtained further supplementary information identifying the corresponding TRAU unit 3 or the corresponding A interface circuit, and forwarded the supplementary information to the operation and maintenance unit 22 of the BSC2 as a timeout message supplementary parameter; in short, the timeout message forwarded to the BSC operation and maintenance unit 22 contains sufficient information The ID corresponds to the information parameter of the TRAU unit 3 or the A interface circuit, and is used by the BSS system maintenance personnel to locate the related TRAU unit 3 or A interface circuit problem as accurately as possible.

When the control unit 21 of BSC2 does not receive the BTS1 uplink service information message within the set period of the continuous inactive timer threshold reported by TRAU unit 3, the control unit 21 of BSC2 sends a response corresponding to TRAU unit 3 to the MSC5 side. The reset message of the A interface circuit returns the states of BSC2 and MSC5 on both sides of the A interface circuit to the idle state, which prevents the A interface circuit from being unavailable for a long time due to an abnormality on the MSC5 side, thereby avoiding waste of resources of the related A interface circuit. .

The reset of the A interface circuit means that the A interface circuit changes from a busy state (BUSY) to an idle state. (IDLE), because TRAU vehicle unit 3 cannot receive the various types of uplink service frame information sent by BTS1 for a period of time, TRAU unit 3 changes from a service functional state to a non-service functional state. Here, a period of time is generally tens of milliseconds to hundreds of milliseconds. The service functional state refers to code conversion of voice services and rate adaptation of data services.

After that, if the uplink service information sent by BTS1, that is, various types of TRAU frames, is not received, a timeout message may be sent to the control unit 21 of BSC2 through the TRAU uplink maintenance channel 26 at a certain period. The sending period of the timeout message is set. It depends on the processing capacity of the control unit 21 of the BSC2 and the total amount of alarm messages.

In BSC2, because the relay device of the A interface circuit is identified to be faulty, or the A interface circuit is blocked for maintenance operation, or a message that the MSC5 is blocked in the A interface circuit is received, when the state of the related A interface circuit is set to a non-idle state, BSC2 controls The unit 21 issues a command to turn off the timer through the downlink maintenance channel 25 of the TRAU unit 3 corresponding to the interface circuit of the relevant part, so that the timer of this part of the TRAU unit 3 is always non-timed, so as to avoid false alarm messages in this part of the TRAU unit 3.

When BSC2 recognizes that the A-interface circuit relay equipment is restored, or performs maintenance operations on the A-interface circuit, or receives a message that MSC5 releases or resets the A-interface circuit, the related A-interface circuit state is reset to the idle state, and BSC2 The control unit 21 issues a command to open the timer through the downlink maintenance channel 25 of the TRAU unit corresponding to the interface circuit of the relevant part A, so that the timer of this part of the TRAU unit 3 restarts working.

The timer timeout threshold cannot be less than the maximum time interval for the corresponding A interface circuit to be repeatedly selected. Otherwise, a false alarm message for timer timeout may be reported, that is, the above abnormal timeout false alarm message may be reported under normal use of the A interface circuit.

The timer timeout threshold can be configured by the BSC2 operation and maintenance unit 22. The BSC2 operation and maintenance unit 22 is sent to the BSC2 control unit 21 through the BSC control unit downlink maintenance channel 23, and the BSC2 control unit 21 passes The row maintenance channel 25 is forwarded to the TRAU unit 3 corresponding to each A interface circuit. The timers of the TRAU unit 3 corresponding to each A interface circuit can be set to different values, but the timeout threshold of the timer of each TRAU unit 3 must be greater than the maximum time interval for the corresponding A interface circuit to repeatedly select.

Due to the large dynamic range of the traffic volume during the twenty-four hours of a day, it is possible to distinguish the traffic characteristics of each time period, and the traffic characteristics of day and night. Therefore, different timeout thresholds can be set on the timer by BSC2 to improve the above problems. Timeliness of identification. When the timeout threshold is reset, the control unit 21 of the BSC2 clears the message to the timer of the related TRAU unit 3 through the TRAU downlink maintenance channel 25. In this way, when the MSC5 selects the A interface circuit as the round-robin mode, the timer timeout threshold of all TRAU units 3 corresponding to all the A interface circuits corresponding to the BSC2 side can be set to twenty-four hours.

The above description is only the preferred embodiments of the present invention, and is not intended to limit the protection scope of the present invention.

Claims

Claim

1. A method for monitoring an A interface circuit in a wireless communication system, each corresponding to a code conversion and rate adaptation unit (TRAU) of an A interface circuit between a base station subsystem (BSS) and a network subsystem (NSS). When the service frame information sent to the base station system (BTS) side, normal services are started through in-band activation; when the TRAU unit does not receive the service frame information sent from the BTS side for a period of time, the TRAU unit is set Non-business state; characterized in that the method includes the following steps:

A TRAU unit continuous inactive timer is set in each TRAU unit, and the timer is set by the operation and maintenance unit of the base station controller (BSC). At the same time, the timer is set to be entered in the TRAU unit. ^ "Keep non-timed during normal business, start timing when TRAU unit is set to non-business state, and keep timed state while TRAU unit is in non-business state;

When the current value of the timer is equal to the set threshold value, the TRAU unit reports a timeout message to the BSC for locating a problem with the A interface circuit.

2. The monitoring method according to claim 1, wherein the A interface circuit corresponding to each TRAU unit is selected for use with a certain polling cycle.

3. The monitoring method according to claim 2, wherein the threshold of the continuous inactive timer of the TRAU unit is greater than the maximum time interval at which the corresponding A interface circuit is repeatedly selected in the polling cycle. .

4. The monitoring method according to claim 3, wherein a threshold value of the continuous inactive timer of the TRAU unit is set to 24 hours.

5. The monitoring method according to claim 1, wherein after the operation and maintenance unit of the BSC sets a threshold of a continuous inactive timer of the TRAU unit, the method further comprises: the operation and maintenance unit performs downlink maintenance through the BSC control unit The channel assigns the timer The configuration information is sent to the control unit of the BSC, and the control unit of the BSC forwards the configuration information to the TRAU unit corresponding to each A interface circuit through each TRAU downlink maintenance channel.

6. The monitoring method according to claim 1, wherein, during the timing of the timer, when the BSC recognizes that the A-interface circuit relay device is faulty, or performs blocking maintenance operations on the A-interface circuit, or receives When the message to the mobile switching center is blocking the A interface circuit, the method further includes: setting the state of the related A interface circuit to a non-idle state, and at the same time, the control unit of the BSC sends the timer to the timer through the TRAU downlink maintenance channel corresponding to the TRAU unit of the related A interface circuit. Command to stop timing.

7. The monitoring method according to claim 1, wherein, when the timer is in a non-timed state, when the BSC recognizes that the A-interface circuit relay device is restored, or performs maintenance operations on the A-interface circuit to be closed, or When receiving the message that the mobile switching center unblocks or resets the A interface circuit, the method further includes: setting the state of the related A interface circuit to an idle state, and at the same time, the control unit of the BSC responds to the TRAU downlink maintenance channel of the TRAU unit through the related A interface circuit. The timer sends a command to start timing.

8. The monitoring method according to claim 1, wherein the timeout message reported by the TRAU unit carries parameters and information identifying a corresponding TRAU unit or a corresponding A interface circuit.

9. The monitoring method according to claim 1, further comprising: when the control unit of the BSC does not receive the uplink service information of the BTS within the set timer threshold time, the control unit of the BSC A reset message corresponding to the A interface circuit of the TRAU unit is sent to the mobile switching center (MSC) side, and the states of the BSC and MSC on both sides of the A interface circuit are set to the idle state.

10. The monitoring method according to claim 1 or 9, wherein the TRAU unit has not received the uplink service from the BTS after exceeding the set timer threshold time. Information, a timeout message is sent to the control unit of the BSC through the TRAU uplink maintenance channel at a certain period.

11. The monitoring method according to claim 1, further comprising: after resetting the timeout threshold of the continuous inactive timer of the TRAU unit, the control unit of the BSC sends a report to the TRAU downlink maintenance channel to The relevant TRAU unit sends a timer clear message.

12. The monitoring method according to claim 1, wherein the TRAU unit is a TRAU unit implemented in an embedded manner.

13. The monitoring method according to claim 1, further comprising: after the TRAU unit reports a timeout message to the control unit of the BSC through the TRAU uplink maintenance channel, the control unit of the BSC then uplinks through the BSC control unit. The maintenance channel forwards the timeout message to the BSC's operation and maintenance unit.